The projects outlined in this application extensively utilize genetically altered mice to explore the molecular genetic basis of pediatric liver disease in vivo. Project 1 will examine the effects on the liver of the mutant alpha1-anti-trypsin Z molecule, which is retained in the endoplasmic reticulum of liver cells. Mice will be created carrying transgenes that allow timed induction of the mutant protein specifically in the liver, therein providing a mammalian model of the human disease that is amenable to experimental manipulation. Project 3 will utilize transgenes to investigate transcriptional regulation of the linked genes encoding the two subunits of the trifunctional proteins. Since these genes are expressed in multiple tissues and share a promoter, definitive assignation of transcriptional regulatory elements must be determined in vivo. This project will also create an animal model with targeted mutation of long chain 3-acyl-CoA dehydrogenase (LCHAD) activity to define the pathogenesis of maternal liver disease during pregnancy characteristic of human LCHAD deficiency and acute fatty liver of pregnancy. Finally Project 4 will determine the precise function of the copper chaperone HAH1 in copper transport and metabolism in the whole animal by targeted gene disruption. The manipulations to accomplish these studies involve the techniques of pro-nuclear injection to create transgenic animals and ES cell injection into blastocysts to create chimeric animals. In addition, embryos from these genetically altered animals will need to be frozen for long-term maintenance Since successful execution of these techniques requires both expensive equipment and extensive training of technical personnel, we will utilize a central laboratory to concentrate expertise and share costs. This laboratory will provide expertise, advice, and assistance in the generation and maintenance of genetically altered mice, including prompt and reliable performance of the following techniques: production of transgenic mice by pro-nuclear injection of DNA construction, production of chimeric mice by blastocyst injection of embryonic stem cells, preservation of mutant mouse stock by embryo cryopreservation, and access to mouse breeding stocks.